<!DOCTYPE html>
<html lang="zh-CN">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    * {
      margin: 0;
      padding: 0;
    }

    .header {
      width: 100%;
      height: 300px;
      background-color: orange;
    }

    .father {
      height: 250px;
    }

    .nav {
      width: 100%;
      position: sticky;
      top: 100px;
      height: 200px;
      background-color: pink;
    }

    .main {
      width: 100%;
      height: 100px;
      background-color: skyblue;
    }
  </style>
</head>

<body>
  <div class="header">我是头部</div>
  <div class="father">
    <div class="nav">我是导航</div>
  </div>

  <div class="container">
    <div class="main">我是主体部分1</div>
    <div class="main">我是主体部分2</div>
    <div class="main">我是主体部分3</div>
    <div class="main">我是主体部分4</div>
    <div class="main">我是主体部分5</div>
    <div class="main">我是主体部分6</div>
    <div class="main">我是主体部分7</div>
    <div class="main">我是主体部分8</div>
  </div>
</body>

</html>